Metal shaving tool



Nov. 3, 1959 1 JR 2,910,920

METAL SHAVING TOOL Filed Aug. 4, 1958 INVENTOR.

Arnclud P. Bidurr Jr.

BY MM A Nor/rays United States Patent METAL SHAVING TOOL Amaud P.Bidart, Jr., Los Angeles, Calif., assignor to Zephyr Manufacturing C0,,Inglewood, Calif., a copartnership Application August 4, 1958, SerialNo. 752,887

2 Claims. (Cl. 90-12) This invention has to do generally with millingtools and relates more particularly to a hand-manipulated tool of thetype generally referred to as a shaver,- being peculiarly adapted formachining or shaving otf projections on work sheets. For instance, afield in which my tool finds considerable use is in the aircraftmanufacturing industry, where it is used to shave rivet heads projectingfrom sheets so that they become flush with the surrounding sheetsurface.

I am aware that tools of this general type are well known in the art,but those of which I am aware have possessed certain shortcomings inthat it is difficult to initially, accurately position the tool over theprojection to be shaved with proper evenness and flushness. Also, thoseprior tools of which I am aware, do not provide means for automaticallyretracting the cutting element when it is not being applied to work,which means are very important to avoid personal injuries to workersoperating such tools. An additional shortcoming of prior tools of thischaracter is that they do not have efficient means for readily andaccurately adjusting the tool to a predetermined depth of cut so as toprevent cutting below the plane of the surface of the work sheet. Stillanother shortcoming of prior tools is that they tend to become cloggedwith metal cuttings produced by the cutting operation.

It is, therefore, among the objects of my invention to provide a tool ofthis character incorporating a resiliently mounted, easily adjustable,nose member or cutter guard, which enables the tool to be positioned inproper flush relation with or perpendicular to the sheet surface fromwhich the projection being shaved extends; the adjustable nose piecefunctioning automatically to retract the cutter when not being used, aswell as to limit the depth of the cut.

Another object is the means which I provide for utilizing the airexhausted from the air motor, conventionally used to operate such tools,for the purpose of con stantly blowing out of the tool cuttings as theyare produced by the cutter, and, in this connection, the novel nosepiece of my tool is particularly constructed to facilitate the carryingout of this purpose.

While I shall point out in the appended claims the features andcombinations which I consider to be new, I shall now, for the purpose ofenabling those skilled in the art to make and use it, describe apresently preferred embodiment of my invention, for which purpose Ishall refer to the accompanying drawing, wherein:

Fig. 1 is a side elevation;

Fig. 2 is an enlarged sectional view taken on line 2-2 of Fig. 3; and

Fig. 3 is a view taken on line 3-3 of Fig. 2.

Referring now to the drawing, I show a hand-manipulated tool of the guntype, comprising a body 5 in the upper part of which there is mounted aconventional air motor, not illustrated in the drawing because anyconventional air motor will suffice for the purpose of my invention. Thehandle portion 5a of the body car- 2,910,920 Patented Nov. 3, 1959 riesa spring-loaded trigger plunger 6 for manipulating the valve (not shown)controlling the air line leading to the motor.

Threaded into the internally threaded bottom flange portion 15 of theupper part of the body, there is a housing member 17 carrying ballbearings 19 (only one of which is shown) for journaling a drive shaft 20driven by the air motor.

The lower end of the housing member 17 presents an annular cavity 22 inwhich a ring gear 24 is mounted, the ring gear being free to rotate inthe cavity, but being secured, as by pins 25, to a cage 30 which isrotatably carried in a sleeve 32 threaded onto the housing member 17.

For rotatably actuating the cage 30, I provide the drive shaft 20 with aworm thread 35 engaging a worm gear 36, rotatably mounted on stub shaft37 whose outer end portion is fitted in a radial hole 38 through thehousing member 17. Gear 36 meshes with a gear 40 secured on a shaft 42whose bottom end carries a gear 43 which meshes with and rotates thering gear to impart rotation to the cage 30 about the axis of the bodywhile thecutter, to be hereinafter described, is rotated about an axisnormal to the latter axis, for stabilizing purposes. As will be seen inthe drawing, the gears 36 and 37 and the Worm threaded portion 35 aredisposed in a recess 45 in the housing member 17.

The bottom end of the drive shaft 20 has secured to it a beveled gear 50which meshes with and drives another beveled gear 51 fixed on ahorizontal shaft 53 journaled in ball bearings 54 in the cage.

The leftend of shaft 53 has secured on ita gear 57 which drives a pairof gears 58, 59, the latter gear being secured on a cutter shaft 60journaled in ball bearings 61. A cutter wheel 65 is secured on shaft 60,there being spacer sleeves 66, 67 interposed between the ends of thecutter and the bearings.

A nose assembly, generally denoted 70, comprises an inner sleeve 72axially slotted at 73. This sleeve is slidably mounted on the sleeve 32and is yieldably urged downwardly or protractively by a coil spring 75.A nose piece 77 is threaded onto the inner sleeve 72 for purposes ofadjustment axially relative thereto, the top end of the nose piecehaving upwardly projecting teeth 80.

A lock ring 82 is slidably mounted on the inner sleeve 72 and has anenlarged diameter bottom end portion 83 engaging over the top endportion of the nose piece. This lock ring has an annular row ofdepending teeth 84 which normally mesh with teeth so that, when theteeth are engaged, the nose piece is retained by the lock ring againstrotation. The lock ring is held against rotation by a set screw 87threaded through a sleeve frictionally fitted on sleeve 32, the screwextending through an axial slot 88 in the lock ring, as Well as throughthe previously described slot 73 in the sleeve 72. The lock ring isyieldably urged downwardly against the outer end portion of the nosepiece by a coil spring 90, which is relatively more stiff than thepreviously described spring 75.

The bottom end wall 91 of the nose piece has a central aperture 92centered below the cutter 65. As will be noted from the drawing, thebottom end wall 91 of the nose piece is made in two parts, the innerpart 91a being threaded into the surrounding part 91b.

As best shown in Fig. 2, the air exhausted from the air motor is passeddownwardly through a port 95 which discharges into an annular channel 96in the upper end of the cage, and from this channel the air is passed ondownwardly through a port 97, discharging directly about the cutter 65.

Operation of the device is as follows: to adjust the nose piece toenable the cutter to cut to the desired depth, the

. 3 lock ring is first manually moved upwardly against th pressure ofspring 90 to disengage the teeth 80, 84. Then the nose piece is manuallyrotated until the desired distance is provided between the peripheral orcutting surface of the cutter and the bottom plane of the wall 91a ofthe nose piece, after which the locking ring is released to reengagesaid teeth and thus lock the nose piece against further rotationrelative to the inner sleeve. To facilitate meticulous adjustment, Iprovide adjustment scale indicia 98 around the periphery of the nosepiece and a cooperating marker 99 on the lock ring.

To begin the shaving operation, the tool is manually placed over theprojection to be shaved with the projection substantially centered intheaperture 92 beneath the cutter. In this position, the bottom wall of thenose piece around the aperture engages the surface of the sheet aroundthe projection, while the cutter engages the projection. The operatorthen manually manipulates the trigger plunger 86 to actuate the airmotor and thereby rotate the cutter. As the shaving operation proceedsto grind or shave away the projection; the nose piece will be graduallyforced upwardly against the pressure of spring 75 until the sleeve 72abuts the set screw 87, which limits the depth to which the cutting cango. In the course of this operation, the cage 30 with its carried partsis rotated about the axis of the body while the cutter rotates about anaxis normal thereto, so that the tool is stabilized. The air exhaustedfrom the air motor blows the cuttings out from about the cutter andthrough the openings 100, provided in the bottom end of the nose pieceat and adjacent the periphery of the latter.

I claim:

1. A shaving tool for machining ofl? that portion of a rivet or the likewhich projects outwardly beyond the surface of a riveted article,comprising a body including an upper portion having a sleeve portiondepending therefrom and a cage portion mounted for rotation in andrelative to said sleeve portion, a cutter wheel mounted in said cageportion for rotation about an axis normal to the axis of rotation ofsaid cage portion, means for simultaneously rotating said cage portionand said cutter wheel about their respective axes, said cutter wheelhaving its cutting surface exposed at thje bottom of said cage, a noseassembly carried by the bottom end portion of said sleeve, including anexteriorl'y threaded second sleeve slidably rnounted on said firstmentioned sleeve, resilient means yieldably urging said second leevedownwardlyof said first mentioned sleeve, a cup shaped nose piece havinga sidewall adjustably threadedly mounted on said second sleeve and abottom end wall having an aperture normally underlying said cutting.surface of said cutter wheel, and means for releasably locking saidnose piece in adjusted position relative to and axially of said sleeve.

2. The tool of claim 1 wherein said means for releasably locking saidnose piece in adjusted position relative to said second sleeve includesa locking sleeve slidably mounted on said second sleeve coaxial with andin normal end-to-end abutting relationship to said nose piece, and thecontiguous end portions of said locking ring and said nose piece havingnormally inter-engaging teeth, spring means yieldably urging said teethinto interengagement, and means securing said locking sleeve againstrotation relative to said nose piece.

References Cited in the file of this patent

